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The exterior angles of a triangle is 130...

The exterior angles of a triangle is `130^(@)` and the two interior opposite angle are in the ratio 6:7. find the angles of the triangle.

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To solve the problem, we need to find the angles of a triangle given that one of its exterior angles is \(130^\circ\) and the two interior opposite angles are in the ratio \(6:7\). ### Step-by-Step Solution: 1. **Understanding the Exterior Angle**: The exterior angle of a triangle is equal to the sum of the two opposite interior angles. In this case, the exterior angle \( \angle CAD \) is given as \(130^\circ\). 2. **Finding the Interior Angle**: According to the property of triangles, the sum of the interior angle \( \angle BAC \) and the exterior angle \( \angle CAD \) is \(180^\circ\). \[ \angle BAC + \angle CAD = 180^\circ \] Substituting the value of the exterior angle: \[ \angle BAC + 130^\circ = 180^\circ \] Therefore, \[ \angle BAC = 180^\circ - 130^\circ = 50^\circ \] 3. **Setting Up the Ratio**: Let the two interior angles \( \angle ABC \) and \( \angle ACB \) be represented as \(6x\) and \(7x\) respectively, based on the ratio \(6:7\). 4. **Applying the Angle Sum Property**: The sum of the angles in a triangle is \(180^\circ\). Therefore, we can write: \[ \angle BAC + \angle ABC + \angle ACB = 180^\circ \] Substituting the known values: \[ 50^\circ + 6x + 7x = 180^\circ \] Simplifying this gives: \[ 50^\circ + 13x = 180^\circ \] 5. **Solving for \(x\)**: Rearranging the equation: \[ 13x = 180^\circ - 50^\circ \] \[ 13x = 130^\circ \] Dividing both sides by 13: \[ x = \frac{130^\circ}{13} = 10^\circ \] 6. **Finding the Angles**: Now substituting \(x\) back to find the angles: - \( \angle ABC = 6x = 6 \times 10^\circ = 60^\circ \) - \( \angle ACB = 7x = 7 \times 10^\circ = 70^\circ \) 7. **Final Angles of the Triangle**: The angles of the triangle are: - \( \angle BAC = 50^\circ \) - \( \angle ABC = 60^\circ \) - \( \angle ACB = 70^\circ \) ### Summary of the Angles: - \( \angle BAC = 50^\circ \) - \( \angle ABC = 60^\circ \) - \( \angle ACB = 70^\circ \)
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